SIJ & TMD

Question 1

TMJ Range

Answer 1

• Opening
  
  • WNL: 4 fingers / 3 knuckles (non-dominant hand) men 40-45mm; women 45-50mm
  • Functional: 3 fingers / 2 knuckles
• Lateral deviation
  
  • 1/4 opening
• Protrusion 5 mm

Question 2

Muscles

Answer 2

• Elevation:
  
  • masseter, temporalis, medial pterygoid
  • Superior belly lateral pterygoid active during closing (stabilizes disc)
• Dpressors
  
  • inferior belly lateral pterygoid, digastric, mylohyoid, geniohyoid, stylohyoid
• Deviation:
  
  • ipsilateral temporalis
  • Contralateral medial & lateral pterygoid

Question 3

Kinematics

Answer 3

11-25 mm opening, mandibular condyle rotates anteriorly

25mm to end range, mandibular condyle translates anteriorly

Question 4

TMD problems

Answer 4

• Internal derangement (C-curve=capsular):
  
  • Anterior disk displacement WITH reduction
    
    • 2 clicks (opening & closing)
    • Pain, limited opening TO involved side
  • Anterior disk displacement withOUT reduction
    
    • 0 clicks
    • “closed lock”
  • Posterior disk displacement
    
    • “open lock” (also overstretched lateral pterygoid)
• S-curve
  
  • muscle imbalance
• Headaches

Question 5

TMD interventions

Answer 5

• Education
  
  • including cognitive behavioral therapy
• Manual therapy
  
  • STM
  • Joint mobs (c-spine too)
• soft diet
• exercise
  
  • “safe opening”
  • posture
  • ADDwR (Yoda et al)
    
    • Mouth maximal opening with click, then close mouth along a protruded path. Contact teeth,carefully retrude the condyle BEFORE closing click occurs. (disk repositioning mandibular position). Last open mouth maximally again without an opening click.